1. Describe how crystals
li. Why should curd and other sour substances not be kept in
aluminium or copper containers ?
Why is water essential for plants ?
Answers
ii) Curd and sour substances contain acids. Acids react with metals to produce salt and hydrogen gas. So, if such substances are kept in copper container, the acid will react and the container will be corroded.
iii) Water is vital for the life and survival of all plants.
Water is also essential for the transportation of nutrients and sugars from the soil to the plants. All plants will suffer from water shortage or drought at some point. This can be fatal in some cases or severely slow the growth of those plants. Plants suffering from a prolonged drought can be left susceptible to secondary infection by pests and pathogens.
(Please write the first question correctly)
☆ANSWERS☆
Qus: Describe how crystals?
Ans: Crystallization is the process by which we can obtain crystals of copper sulphate. In this process, a few drops of dilute sulphuric acid is added to water. The water is then boiled & as it starts boiling, copper sulphate powder is added with stirring. The powder must be added on till the solution becomes saturated.
Qus: Why should curd and other sour substances not be kept in
aluminium or copper containers ?
Ans: Curd and sour substances should not kept in copper and brass vessels because they contain acid which can react with metals and form salts.
Qus: Why is water essential for plants ?
Ans: Plants need water to grow! Plants are about 80-95% water and need water for multiple reasons as they grow including for photosynthesis, for cooling, and to transport minerals and nutrients from the soil and into the plant. "We can grow food without fossil fuels, but we cannot grow food without water."